Track your caffeine.
See the real curve.
CaffCurve shows exactly what caffeine is doing in your body — hour by hour. Watch the decay. Track your sleep protection score. Finally understand why you can't sleep.
Sleep protection score: 78 ↑
Three steps to better sleep.
Log your drink
QuickAdd your usual coffee, energy drink, or tea in one tap. Don't see it? Add your own with its own caffeine amount.
Watch the decay curve
Your personal decay curve updates in real time using caffeine's actual half-life. See when you'll peak, when you'll crash, and when it's safe to sleep.
Improve your sleep protection score
Every good caffeine decision improves your daily score. Build streaks. Unlock achievements. Watch your trend improve over time. The score is an estimate from your caffeine timing, not a measurement of your sleep.
See it in action
The curve, your trends, and your sleep protection score, as they look in the app.
Everything you need. Nothing you don't.
Real-time decay curve
Based on caffeine's 5–6 hour half-life. See exactly what's happening in your body right now.
Sleep protection score & streaks
A daily score that rewards good timing. Build streaks. Watch your trend improve.
Milestones & achievements
Unlock badges as your habits improve. Gamification that actually motivates.
QuickAdd
Log your usual drinks in a single tap. Add your own for anything that's not on the list.
History & trends
See your patterns weekly and monthly. Correlate caffeine with sleep quality.
Privacy first
Your caffeine data stays on your device. No account needed. Optional iCloud Sync. Built in Switzerland.
CaffCurve is an informational tool, not a medical device. The caffeine decay model is a general approximation based on average caffeine metabolism (5–6 hour half-life). Individual metabolism varies significantly based on genetics, medication, liver function, and tolerance. CaffCurve does not provide medical advice. Users with health conditions, caffeine sensitivity, pregnancy, or who are taking medications should consult a healthcare professional before making changes to their caffeine intake.
Simple pricing.
Try everything free for 1 week, then choose a plan.
Billed monthly
- Real-time caffeine decay curve
- Bedtime caffeine projection
- Last safe drink time
- QuickAdd + custom drinks
- Badges & streaks
- Full history & trends
- Half-life customization
1-week free trial · Cancel anytime in your Apple ID settings
≈ $3.32 / month, billed annually
- Real-time caffeine decay curve
- Bedtime caffeine projection
- Last safe drink time
- QuickAdd + custom drinks
- Badges & streaks
- Full history & trends
- Half-life customization
1-week free trial · Cancel anytime in your Apple ID settings
Prices shown in USD. Local prices vary by country and are shown in the App Store before you subscribe.
Questions? hello@jappjstudio.app
Common questions.
How does the free trial work?
Every new subscriber gets a 1-week free trial with full access to all features. After the trial you're charged $4.90/month or $39.90/year, depending on the plan you chose, unless you cancel at least 24 hours before the trial ends. You subscribe with the payment method on your Apple ID, and you can cancel anytime in your Apple ID settings. Prices are shown in USD; the App Store shows the exact price in your currency before you subscribe.
How do I cancel?
Subscriptions are managed through your Apple ID. Open Settings → [your name] → Subscriptions → CaffCurve and tap Cancel Subscription. Cancel at least 24 hours before the end of the trial or billing period to avoid the next charge. You keep access until the period ends.
Do I need to create an account?
No account required. Your caffeine logs are stored on your device and are never sent anywhere.
Does CaffCurve see my caffeine data?
No. Your caffeine logs, drinks and sleep settings stay on your device (and in your own private iCloud if you turn on iCloud Sync). They are never sent to JappJ Studio. The only data that leaves your device is anonymous subscription analytics (purchase events under a random ID, no health data), processed by RevenueCat. Details are in the Privacy Policy.
Is this medical advice?
No. CaffCurve is an informational wellness tool, not a medical device. Its caffeine and bedtime figures are estimates based on average metabolism, and the sleep protection score is calculated from your caffeine timing, not measured from your actual sleep. If you have a health condition, are pregnant or take medication, ask a healthcare professional.
How accurate is the caffeine decay model?
The model uses caffeine's average 5–6 hour half-life, which is well-established in scientific literature. You can adjust the half-life in settings to match your personal metabolism. CaffCurve is an informational tool, not a medical device.
What drinks can I track?
CaffCurve ships with a small set of common drinks (espresso, filter coffee, energy drinks, tea) you can QuickAdd in one tap. Don't see your drink? Add it yourself with its own caffeine amount — it's saved for next time.